Service transmission in a Long Term Evolution (LTE) system may be scheduled based on a base station (e.g., an eNodeB or eNB). A basic time unit for scheduling may be a subframe, and one subframe may include multiple time domain symbols. In a specific scheduling procedure, the base station may send control information on a control channel, such as a physical downlink control channel (PDCCH) or an enhanced physical downlink control channel (EPDCCH). The control channel may carry scheduling information of a physical downlink shared channel (PDSCH) or a physical uplink shared channel (PUSCH). Scheduling information may include control information such as resource allocation information and coding scheme adjustment. A user equipment (UE) detects the control channel in a subframe, and receives a downlink data channel or sends an uplink data channel according to the scheduling information carried in the detected control channel.
LTE supports a carrier aggregation (CA) technology, where an eNB configures multiple carriers for one UE to improve a data rate of the UE. In order for the eNB to perform scheduling for the UE and send downlink data to the UE on multiple downlink carriers, the UE may need to feed back channel state information (CSI) of the carriers to the eNB using a physical uplink control channel (PUCCH) resource or a PUSCH resource. Due to a format limitation of an uplink control channel, usually, the UE may feed back only periodic CSI that has a highest priority on a carrier. For periodic CSI of multiple downlink carriers that has a same priority, periodic CSI of a carrier that has a smallest downlink component carrier index may be fed back. In a particular uplink subframe, the eNB may configure that a scheduling request (SR) needs to be fed back in the uplink subframe, and the SR is used to request an uplink shared channel (UL-SCH) resource from the eNB.
In the prior art, it may be preconfigured that a UE does not support simultaneous sending of a PUCCH and a PUSCH; or it may be preconfigured that the UE supports simultaneous sending of a PUCCH and a PUSCH, but when no PUSCH is scheduled, periodic CSI may be discarded in cases when the periodic CSI and an SR need to be sent simultaneously in a same subframe, or when HARQ-ACK feedback information of a primary component carrier in multiple carriers needs to be sent in the same subframe, or when HARQ-ACK feedback information of carriers whose quantity is not greater than a preset quantity in the multiple carriers needs to be sent in the same subframe. Consequently, when the eNB configures a relatively large quantity of carriers, a large amount of periodic CSI information may be discarded, and thus periodic CSI information on a large quantity of carriers is lost, affecting accuracy of scheduling by the eNB for the UE.